Incorporation of spray-dried encapsulated bioactive peptides from coconut (Cocos nucifera L.) meal by-product in bread formulation.

This study aimed to stabilize and mask the bitterness of peptides obtained from the enzymatic hydrolysis of coconut-meal protein with maltodextrin (MD) and maltodextrin-pectin (MD-P) as carriers via spray-drying. Essential (~35%), hydrophobic (~32%), antioxidant (~15%), and bitter (~45%) amino acids comprised a significant fraction of the peptide composition (with a degree of hydrolysis of 33%). The results indicated that the peptide's production efficiency, physical and functional properties, and hygroscopicity improved after spray-drying. Morphological features of free peptides (fragile and porous structures), spray-dried with MD (wrinkled with indented structures), and MD-P combination (relatively spherical particles with smooth surfaces) were influenced by the process type and feed composition. Adding free and microencapsulated peptides to the bread formula (2% W/W) caused changes in moisture content (35%-43%), water activity (0.89-0.94), textural properties (1-1.6 N), specific volume (5.5-6 cm3/g), porosity (18%-27%), and color indices of the fortified product. MD-P encapsulated peptides in bread fortification resulted in thermal stability and increased antioxidant activity (DPPH and ABTS+ radical scavenging: 4.5%-39.4% and 31.6%-46.8%, respectively). MD-P (as a carrier) could maintain sensory characteristics and mask the bitterness of peptides in the fortified bread. The results of this research can be used to produce functional food and diet formulations.

Enhancing Encapsulation Efficiency of Chavir Essential Oil via Enzymatic Hydrolysis and Ultrasonication of Whey Protein Concentrate-Maltodextrin.

This study focused on the characterization of emulsions and microparticles encapsulating Chavir essential oil (EO) by application of modified whey protein concentrate-maltodextrin (WPC-MD). Different physical, chemical, morphological, thermal, and antioxidant properties and release behavior of spray-dried microparticles were assessed. Antioxidant, solubility, emulsifying, and foaming activities of modified WPC were increased compared to those of primary material. The results indicated that the particle size distribution varied depending on the type of carriers used, with the smallest particles formed by hydrolyzed WPC (HWPC). Binary blends of modified WPC-MD led to improved particle sizes. The spray-drying yield ranged from 64.1% to 85.0%, with higher yields observed for blends of MD with sonicated WPC (UWPC). Microparticles prepared from primary WPC showed irregular and wrinkled surfaces with indentations and pores, indicating a less uniform morphology. The UWPC as a wall material led to microparticles with increased small cracks and holes on their surface. However, HWPC negatively affected the integrity of the microparticles, resulting in broken particles with irregular shapes and surface cracks, indicating poor microcapsule formation. Encapsulating EO using WPC-MD increased the thermal stability of EO significantly, enhancing the degradation temperature of EO by 2 to 2.5-fold. The application of primary WPC (alone or in combination with MD) as wall materials produced particles with the lowest antioxidant properties because the EO cannot migrate to the surface of the particles. Enzymatic hydrolysis of WPC negatively impacted microparticle integrity, potentially increasing EO release. These findings underscore the crucial role of wall materials in shaping the physical, morphological, thermal, antioxidant, and release properties of spray-dried microparticles, offering valuable insights for microencapsulation techniques.

Effect of active antimicrobial films on quality parameters and shelf-life of fresh yufka dough.

This research aimed to develop polypropylene (PP) antimicrobial films loaded with different concentrations of sorbic acid (SA) for packaging of fresh yufka dough. PP-SA at 6% showed improved mechanical, UV absorption, and moisture barrier properties. Also, the obtained films exhibited in vitro antibacterial and anti-mold properties. Moisture content and aw of packaged dough with different types of active films were not significantly changed upon storage period. Extended storage of dough layered with PP-SA films at concentrations 0-4% for 45 days led to significant decrease of pH from 5.75 in fresh dough to 5.05 in control (p < 0.05). Color attributes including yellowness and whiteness indices of dough were declined and increased, respectively as function of prolonged storage and increase in the concentration of SA. The growth of aerobic psychrotrophic bacteria and filamentous fungi were significantly retarded in yufka dough packaged with PP-SA6% film compared to that packaged with control as well as PP-SA2-4% films. Direct addition of SA into the bulk of dough was not effective in preservation of dough against the growth of bacteria and fungi. Application of antimicrobial preservatives in the composition of PP films could be beneficial in preserving fresh foods such as bakery products against spoilage microorganisms.

Application of low-, and medium-molecular weight chitosan for preparation of spray-dried microparticles loaded with Ferulago angulata essential oil: Physicochemical, antioxidant, antibacterial and in-vitro release properties.

The present work aimed at spray-drying encapsulation of Chavir (Ferulago angulata) essential oil (EO) using low-, and medium-molecular weight chitosan. The obtained EO was observed to be mainly composed of ß-ocimene, α-pinene, and bornyl acetate with antioxidant, and antimicrobial activity. The results indicated that stable emulsions with uniform particle size distribution and encapsulation efficiencies higher than 93 % could be prepared using chitosan as feed for spray-drying. In addition, spray-drying resulted in fabricating stable microspheres with yields higher than 50 %, uniform particle size, and encapsulation efficiency exceeding 70 %. The microspheres were fairly soluble and hygroscopic, and exhibited antioxidant and bacteriostatic activities with a biphasic release pattern. FTIR characterisation confirmed successful encapsulation of EO and thermal properties of microspheres indicated enhanced stability of EO after microencapsulation. Overall, it was revealed that molecular weight of chitosan and EO:chitosan ratio affects some physicochemical properties of obtained chitosan microspheres.

Structural modification of poppy-pollen protein as a natural antioxidant, emulsifier and carrier in spray-drying of O/W-emulsion: Physicochemical and oxidative stabilization.

This study was aimed to investigate the efficiency of poppy-pollen (PP) protein and peptides as carrier for spray-drying encapsulation of grape-seed oil (GSO). The composition of amino acids, functional properties and bioactivity (scavenging of DPPH, ABTS, OH, and nitric-oxide radicals, reducing power, total antioxidant, TBARS levels in O/W-emulsion, and chelation of Fe2+ and Cu2+ ions) of PP-protein were affected by the enzymolysis time. Partial enzymolysis (30 min) led to improved solubility, protein surface activity and increased physical stability of GSO/W emulsion (relative to creaming, aggregation and flocculation) during storage. Also, spray-dried emulsions with this type of carrier (H-30) had the highest production yield (~67 %), solubility (~92 %), flowability, encapsulation efficiency (~96 %), reconstitution ability (least size and EE changes), physical and oxidative stability. The evaluation of the chemical structures (FTIR) indicated the formation of hydrogen bonds between the cis-alkene groups of fatty acids and the hydroxyl groups of the amide A and B regions, as well as the trapping of oil in the carrier matrix. SEM images illustrated the effect of native protein carriers (particles with smooth, dents, and hollow surfaces with surface pores), partially (wrinkled and reservoir-type), and strongly (irregular structures, sticky and amorphous agglomerates) hydrolyzed peptides on the morphology of oily-particles. The results of this research indicate the usability of partially hydrolyzed poppy-pollen protein as a source of natural antioxidant, emulsifier, and carrier in the production, stabilization, and encapsulation of oxidation-sensitive bioactive components and emulsions.

Biological stabilization of natural pigment-phytochemical from poppy-pollen (Papaver bracteatum) extract: Functional food formulation.

In this study, poppy-pollen extract (as a novel source of pigment and natural phytochemical) was microencapsulated. The spray-drying process maintained the encapsulation efficiency (EE) of phenolic (84-93%), anthocyanins (71-83%), and also antioxidant activity of extract in inhibiting DPPH (68-80%), ABTS (74-95%), OH (63-74%) radicals and reducing power (84-95%). The results of the Photo- and thermal (40-70˚C) stability of the bioactive compounds (TPC and TAC) indicated the thermal degradation and decomposition of particles' surface compounds during storage. The chemical (FTIR) and morphological analyses respectively revealed the insertion of extract compounds in the carrier matrix and the production of healthy particles with wrinkled structures. An increase in the carrier concentration elevated physical-stability, maintained structural properties, reduced hygroscopicity, and formed liquid/solid bridges or deliquescence phenomenon. The evaluation of the color histogram of the fortified gummy-candies indicated the usability of the spray-dried PP extract in producing an attractive red color with high sensory perception.

Physicochemical, antioxidant, antimicrobial, and in vitro cytotoxic activities of corn pollen protein hydrolysates obtained by different peptidases.

The applications of protein hydrolysates as food preservatives and nutraceutical ingredients have attracted much attention because of their beneficial effects. The interest in these ingredients has shifted toward their biological activities with benefits to human health. Bioactive peptides are known as antioxidant agents that could promote health-promoting effects and prolong food shelf-life beyond their basic nutritional value. Thus, the aim of this study was to investigate antioxidant, antimicrobial, and in vitro cytotoxic properties of corn pollen protein (CPP) hydrolysates obtained by different enzymes. Proteolytic activity in terms of degree of hydrolysis (DH) and SDS-PAGE analysis was measured in pancreatin (H-Pan), pepsin (H-Pep), and trypsin (H-Tri) hydrolysates. Amino acid composition, antioxidant and antimicrobial activities, and cytotoxicity of hydrolysates were evaluated. DH and SDS-PAGE revealed higher proteolytic activity of pepsin compared to other enzymes. Amino acid analysis showed that the functional amino acids such as antioxidant types were most predominant in H-Pep compared to two other samples. Antioxidant activity of hydrolysates was found to be affected by the type of enzyme and the concentration of hydrolysates. There was a significant difference (p < 0.05) between antioxidant activity of different hydrolysates. The highest antioxidant activity in terms of Trolox equivalent antioxidant capacity (0.23-2.75 mM), DPPH (33.3%-64.8%), and hydroxyl (33.7%-63.2%) radical scavenging activities, chelation of iron (33.2%-62.5%) and copper (30.2%-50.5%) metals, and total antioxidant activity (0.65-0.85) was obtained for H-Pep followed by H-Pan and H-Tri samples. Antibacterial tests showed that pepsin-hydrolyzed protein was not significantly (P > 0.05) effective against E. coli at any concentrations, however, it showed significant (P < 0.05) concentration-dependent effect against S. aureus (with inhibition zones of 15-25 mm). Cytotoxicity results revealed that CPP, as a nonhydrolyzed protein, did not generally show antiproliferative activity, however, a significant (P < 0.05) ability of H-Pep hydrolysate in decreasing HT-29 colon cancer cell line viability was seen in a concentration-dependent manner (the lowest cell viability of 32% at 5 mg/mL). Overall, investigating the application of protein-based hydrolysates is one of the possible strategies that govern their applied intentions as preservatives and nutraceuticals in the food and pharmaceutical industries.

Application of structurally modified WPC in combination with maltodextrin for microencapsulation of Roselle (Hibiscus sabdariffa) extract as a natural colorant source for gummy candy.

The aim of this work was to improve the stability of Roselle extract (RE) by spray-drying using maltodextrin (MD) alone, and in combination with WPC in the forms of unmodified and modified (via ultrasonication, UWPC, or enzymatic hydrolysis, HWPC). Enzymatic hydrolysis by improving the surface activity of WPC increased spray-drying yield (75.1 %), and improved physical (flow) and functional (solubility, and emulsifying) properties of obtained microparticles. Degree of hydrolysis of the primary WPC (2.6 %) was increased to 6.1 % and 24.6 % after ultrasonication and hydrolysis, respectively. Both modifications caused a significant increase in the solubility of WPC, in a way that initial solubility (10.6 %, at pH = 5) was significantly increased to 25.5 % in UWPC, and to 87.3 % in HWPC (P < 0.05). Furthermore, emulsifying activity (20.6 m2/g) and emulsifying stability (17 %) indices of primary WPC (at pH = 5) were significantly increased to 32 m2/g and 30 % in UWPC, and to 92.4 m2/g and 69.0 % in HWPC, respectively (P < 0.05). FT-IR analysis indicated successful encapsulation of RE within carriers' matrix. According to FE-SEM study, the surface morphology of microparticles was improved when modified HWPC was used as a carrier. Microencapsulation of RE with HWPC showed the highest contents of total phenolic compounds (13.3 mg GAE/mL), total anthocyanins (9.1 mg C3G/L) as well as a higher retention of antioxidant activity according to ABTS+ (85.0 %) and DPPH (79.5 %) radicals scavenging assays. Considering all properties of microparticles obtained by HWPC next to their color attributes, it can be concluded that HWPC-RE powders could be used as natural colorant and antioxidant source for the fortification of gummy candy. Gummy candy obtained using 6 % concentration of the above powder gave the highest overall sensory scores.

Nanoencapsulation of Chavir (Ferulago angulata) essential oil in chitosan carrier: Investigating physicochemical, morphological, thermal, antimicrobial and release profile of obtained nanoparticles.

The essential oil obtained by steam-distillation from Ferulago angulata (FA) was stabilized by ionic-gelation technique within chitosan nanoparticles (CSNPs). The aim of this study was to investigate different properties of CSNPs loaded with FA essential oil (FAEO). GC-MS analysis detected the major components of FAEO as α-pinene (21.85 %), ß-ocimene (19.37 %), bornyl acetate (10.50 %) and thymol (6.80 %). Due to presence of these components, FAEO showed stronger antibacterial activity against S. aureus and E. coli with MIC values of 0.45 and 2.12 mg/mL, respectively. Chitosan to FAEO ratio of 1: 1.25 exhibited a maximum encapsulation efficiency (60.20 %) and loading capacity (24.5 %) values. By increasing loading ratio from 1:0 to 1:1.25, mean particle size and polydispersity index were significantly (P < 0.05) increased from 175 to 350 nm and 0.184 to 0.32, respectively, while zeta potential was decreased from +43.5 to +19.2 mV, indicating the physical instability of CSNPs at higher FAEO loading concentrations. SEM observation proved successful formation of spherical CSNPs during the nanoencapsulation of EO. FTIR spectroscopy indicated successful physical entrapment of EO within CSNPs. Differential scanning calorimetry also proved the physical entrapment of FAEO into polymeric matrix of chitosan. XRD exhibited a broad peak at 2θ = 19° - 25° in loaded-CSNPs as indication of successful entrapment of FAEO within CSNPs. Thermogravimetric analysis showed that encapsulated essential oil was decomposed at higher temperature than its free from, indicating the success of encapsulation technique in stabilizing FAEO within CSNPs.

Microencapsulation of Yerba mate extract: The efficacy of polysaccharide/protein hydrocolloids on physical, microstructural, functional, and antioxidant properties.

Effects of hydrolyzed whey protein concentrate (WPC) and its combination with polysaccharides as wall material in spray-drying microencapsulation of Yerba mate extract (YME) have not been investigated yet. Therefore, it is hypothesized that the surface-active properties of WPC or WPC-hydrolysate may improve different properties of spray-dried microcapsules (such as physicochemical, structural, functional and morphological properties) compared to neat MD and GA. Thus, the objective of current study was to produce microcapsules loaded with YME by different carrier combinations. Effect of maltodextrin (MD), maltodextrin-gum Arabic (MD-GA), maltodextrin-whey protein concentrate (MD-WPC), and maltodextrin-hydrolyzed WPC (MD-HWPC) as encapsulating hydrocolloids was studied on physicochemical, functional, structural, antioxidant and morphological characteristics of the spray-dried YME. The type of carrier significantly affected spray dying yield. Enzymatic hydrolysis by improving the surface activity of WPC increased its efficiency as a carrier and produced particles with high production yield (about 68 %) and excellent physical, functional, hygroscopicity and flowability indices. Chemical structure characterization by FTIR indicated the placement of phenolic compounds of the extract in the carrier matrix. FE-SEM study showed that the microcapsules produced with polysaccharide-based carriers were completely wrinkled, whereas, the surface morphology of particles was improved when protein-based carriers were applied. Among the produced samples, the highest amount of TPC (3.26 mg GAE/mL), inhibition of DPPH (76.4 %), ABTS (88.1 %) and hydroxyl (78.1 %) free radicals were related to microencapsulated extract with MD-HWPC. The results of this research can be used to stabilize plant extracts and produce powders with appropriate physicochemical properties and biological activity.

Application of oleaster leaves (Elaeagnus angustifolia L.) essential oil and natural nanoparticle preservatives in frankfurter-type sausages: An assessment of quality attributes and stability during refrigerated storage.

The effects of oleaster leave essential oil (OLEOs: 1000 and 2000 ppm) in combination with nisin nanoparticles (200 ppm) and ε-polylysine nanoparticles (2000 ppm) on the physicochemical, microbiological and sensory properties of the emulsion-type sausages without added chemical nitrite/nitrate salts were evaluated during 45 days of storage. Nanoparticle attributes were assessed, including encapsulation efficiency (EE%), zeta potential, nanoparticles size, FTIR analysis, and thermal stability (DSC). Overall, ε-PL nanoparticles (ε-PL-NPs) were thermally more stable and showed higher EE% (91.52%) and zeta potential (37.80%) as compared to nisin nanoparticles (82.85%) and (33.60%), respectively. The use of combined ε-PL-NPs (2000 ppm) + Ni-NPs (200 ppm) with oleaster leaves essential oil (2000 ppm) resulted in a higher pH value (5.88), total phenolic content (10.45 mg/100 g) and lower TBARS (2.11 mg/kg), and also decreased total viable bacteria (1.28 Log CFU/g), Clostridium perfringens (1.43 Log CFU/g), E. coli (0.24 Log CFU/g), Staphylococcus aureus (0.63 Log CFU/g), and molds and yeasts (0.86 Log CFU/g) count in samples at day 45 in comparison to the control (120 ppm nitrite). The consumers approved sensory traits in nitrite-free formulated sausages containing ε-PL-NPs and Ni-NPs combined with OLEOs.

Development and Application of Dual-Sensors Label in Combination with Active Chitosan-Based Coating Incorporating Yarrow Essential Oil for Freshness Monitoring and Shelf-Life Extension of Chicken Fillet.

This study aimed for the application of active chitosan coating incorporating yarrow essential oil (YEO) together with the development of an on-package sensor label based on bromocresol purple (BCP) and methyl red (MR) for shelf-life extension and freshness monitoring of chicken breast fillet. Physiochemical and microbiological attributes of chicken meat coated with sole chitosan, YEO, and chitosan + YEO were compared with those of uncoated (control) samples. Chitosan + YEO coated chicken meat stayed fresh with no significant changes (p > 0.05) in pH (5.42−5.56), TVB-N (12.55−15.36 mg N/100 g), TBARs (0.35−0.40 mg MDA/kg) and total aerobic psycrotrophic bacteria (3.97−4.65 log CFU/g) in days 1−15. There was no response of the dual-sensors label toward the variation in chemical and microbiological indicators of chicken meat coated with chitosan + YEO. However, either uncoated, sole chitosan, or sole YEO treatments indicated a three-stage freshness status with the fresh stage belonged to a period earlier than day 7 (with no distinct color change in both sensor labels); the semi-fresh stage corresponded to storage days between 7−9, wherein a gradual color change appeared (MR from pink to orange, BCP from yellow to light purple); and the spoiled stage occurred in day 9 onward with a drastic color change (MR from orange to light yellow, BCP from light purple to deep purple). In general, the dual-sensors successfully responded to the variation of chemical and microbiological indicators and visual color of uncoated samples during storage time. Based on the obtained results, the application of chitosan + YEO coating efficiently prolonged the freshness of chicken breast meat, where on-package dual-sensors systems were able to detect the freshness stages of meat samples during storage time.

Adsorption ability evaluation of the poly(methacrylic acid-co-acrylamide)/cloisite 30B nanocomposite hydrogel as a new adsorbent for cationic dye removal.

The performance of poly(methacrylic acid-co-acrylamide)/Cloisite 30B nanocomposite (poly(MAA-co-AAm)/Cl30B) hydrogel to adsorb methylene blue (MB) dye from aqueous solutions was investigated and the adsorption efficiency was improved by incorporating Cloisite 30B nanoclays in the adsorbent structure. The hydrogels were analyzed using FTIR, XRD, TGA, and SEM analysis. The effect of adsorbent dose, temperature, initial dye concentration, contact time, and pH on the efficiency of the adsorption process was investigated. Adsorption efficiencies of 98.57 and 97.65% were obtained for poly(MAA-co-AAm)/Cl30B nanocomposite and poly(MAA-co-AAm) hydrogels, respectively. Kinetic study revealed that the adsorption process followed pseudo-first-order kinetic model and α-parameter values of 6.558 and 1.113 mg/g.min were obtained for poly(MAA-co-AAm)/Cl30B nanocomposite and poly(MAA-co-AAm) hydrogels, respectively indicating a higher ability of nanocomposite hydrogel in adsorbing MB-dye. In addition, the results of the intra-particle diffusion model showed that various mechanisms such as intra-particle diffusion and liquid film penetration are important in the adsorption. The Gibbs free energy parameter of adsorption process showed negative values of -256.52 and -84.071 J/mol.K for poly(MAA-co-AAm)/Cl30B nanocomposite and poly(MAA-co-AAm) hydrogels indicating spontaneous nature of the adsorption. The results of enthalpy and entropy showed that the adsorption process was exothermic and random collisions were reduced during the adsorption. The equilibrium data for the adsorption process using poly(MAA-co-AAm)/Cl30B nanocomposite and poly(MAA-co-AAm) hydrogels followed Freundlich and Langmuir isotherm models, respectively. The maximum adsorption capacity values of 32.83 and 21.92 mg/g were obtained for poly(MAA-co-AAm)/Cl30B nanocomposite and poly(MAA-co-AAm) hydrogels, respectively. Higher adsorption capacity of nanocomposite hydrogel was attributed to the presence of Cloisite 30B clay nanoparticles in its structure. In addition, results of RL, n, and E parameters showed that the adsorption process was performed optimally and physically.

Cadmium ion removal from aqueous media using banana peel biochar/Fe3O4/ZIF-67.

In the present study, banana peel waste was used as a suitable source for biochar production. The banana peel biochar (BPB) was modified using Fe3O4 magnetic and ZIF-67 nanoparticles. The modification of the BPB surface (4.70 m2/g) with Fe3O4 and Fe3O4/ZIF-67 significantly increased the specific surface of the nanocomposites (BPB/Fe3O4: 78.83 m2/g, and BPB/Fe3O4/ZIF-67: 1212.40 m2/g). The effect of pH, temperature, contact time, adsorbent dose, and concentration of Cd2+ on the efficiency of the Cd2+ adsorption was explored. Maximum adsorption efficiencies for BPB (97.76%), BPB/Fe3O4 (97.52%), and BPB/Fe3O4/ZIF-67 (99.14%) were obtained at pH 6, Cd2+ concentration of 10 mg/L, times of 80 min, 50 min, and 40 min, and adsorbent doses of 2 g/L, 1.5 g/L, and 1 g/L, respectively. Thermodynamic measurements indicated that the process is spontaneous and exothermic. The maximum capacity of Cd2+ adsorption using BPB, BPB/Fe3O4, and BPB/Fe3O4/ZIF-67 were obtained 20.63 mg/g, 30.33 mg/g, and 50.78 mg/g, respectively. The Cd2+ adsorption using magnetic nanocomposites followed the pseudo-first-order kinetic model. The results showed that studied adsorbents especially BPB/Fe3O4/ZIF-67 have a good ability to adsorb-desorb Cd2+ and clean an effluent containing pollutants.

Development of new magnetic adsorbent of walnut shell ash/starch/Fe3O4 for effective copper ions removal: Treatment of groundwater samples.

The goal of this investigation was to develop a new magnetic nanocomposite of walnut shell ash (WSA)/starch/Fe3O4 to remove Cu (II) present in groundwater samples. The desired nanocomposites were successfully synthesized by the chemical deposition method. The specific active surface area for pristine WSA and WSA/starch/Fe3O4 magnetic nanocomposites was determined to be 8.1 and 52.6 m2/g, respectively. A central composite design for the response surface method was utilized to study the influence of pH, adsorbent quantity, initial content of Cu (II), temperature, and contact time. This method showed the success of the model to design process variables and to estimate the appropriate response. The P- and F-value determined for the quadratic polynomial model showed the significance and accuracy of the proposed model in examining experimental and predicted data with R2 and Adj.R2 of 0.994 and 0.991, respectively. The Cu adsorption onto WSA and WSA/starch/Fe3O4 obeyed the Freundlich and Langmuir models, respectively. The highest Cu (II) sorption capacity of 29.0 and 45.4 mg/g was attained for WSA and WSA/starch/Fe3O4, respectively. The free energy of Gibbs had a negative value at 25-45 °C indicating that the adsorption process is spontaneous. Also, negative ΔH values for copper adsorption showed that the processes are exothermic. The kinetic adsorption data for WSA and WSA/starch/Fe3O4 followed the pseudo-second order (PSO) model. The ability of the composite adsorbent to remove copper from three groundwater samples showed that it could be reused at least 3 times with appropriate efficiency, depending on the water quality.

Impact of high-pressure treatment on casein micelles, whey proteins, fat globules and enzymes activity in dairy products: a review.

The quality and safety of food products are the two factors that most influence the demands made by consumers. Contractual food sterilization and preservation methods often result in unfavorable changes in functional properties of foods. High-pressure processing (HPP) (50-1000 MPa) is a non-thermal preservation technique, which can effectively reduce the activity of spoilage and pathogenic microorganisms with minimal impact on the functional and nutritional properties of food. Comprehensive inquires have disclosed the potential profits of HPP as an alternative to heat treatments by affecting the structure of milk components, particularly proteins and fats. The present paper aims to investigate the effects of HPP on milk components including fats, casein, whey proteins, enzymes, and minerals, as well as on the industrial production of milk and dairy products including cheese, yogurt, ice cream, butter, cream, and probiotic dairy products. HPP allows to extend shelf life of products without the use of additives, meeting current consumer demands. The assurance of microbial safety and the production of food products with minimal changes in quality characteristics (organoleptic, nutritional, and rheological properties) are among its main effects. In addition, the nutritional value of HPP-treated dairy products is also preserved.

Application of waste chalk/CoFe2O4/K2CO3 composite as a reclaimable catalyst for biodiesel generation from sunflower oil.

This investigation aimed to produce a new composited catalyst from a waste chalk powder, a waste generated by the construction industry, to produce biodiesel from sunflower oil. The waste chalk was modified by CoFe2O4 nanoparticles and K2CO3. The surface tests showed that the obtained catalyst has been successfully synthesized with desired surface properties. The surface areas of waste chalk, waste chalk/CoFe2O4, and waste chalk/CoFe2O4/K2CO3 were determined 20.8, 77.8, and 5.8 m2/g, respectively. This indicates that the waste chalk/CoFe2O4/K2CO3 catalyst has a lower surface area due to K2CO3 being placed on the catalyst. Results showed the efficiency of RSM-CCD (R2 = 0.992) compared to ANN (R2 = 0.974). It was shown that a contact time of 180 min, a temperature of 65 °C, a waste chalk/CoFe2O4/K2CO3 mass of 2 wt%, and methanol to oil mole ratio of 15:1 gave the highest efficiency (98.87%) of biodiesel production at the laboratory conditions. The kinetic results of the process showed the energy of activation and frequency factor of 11.8 kJ/mol and 0.78 min-1, respectively. Also, the values of ΔH°, ΔS°, and ΔG° at 65 °C was calculated to be 9010.7 J/mol, -256.3 J/mol and 95.7 kJ/mol, respectively, indicating that the biodiesel production process is endothermic requiring high energy for proceeding. The generated catalyst has an efficiency of over 90% up to 6 steps of reuse. The generated biodiesel was met most of the international standard levels.

Chitosan nanoparticles encapsulating lemongrass (Cymbopogon commutatus) essential oil: Physicochemical, structural, antimicrobial and in-vitro release properties.

This study was aimed to encapsulate lemongrass (Cymbopogon commutatus) essential oil (LGEO) into chitosan nanoparticles (CSNPs) and to investigate their physicochemical, morphological, structural, thermal, antimicrobial and in-vitro release properties. CSNPs exhibited spherical morphology with an average hydrodynamic size of 175-235 nm. Increasing EO loading increased the average size of CSNPs from 174 to 293 nm (at CS:EO ratio from 1:0 to 1:1.25). SEM and AFM confirmed the results obtained by hydrodynamic size indicating that EO loading led to formation of large aggregated NPs. The successful physical entrapment of EO within NPs was shown by fourier-transform infrared spectroscopy. X-ray diffractogram of loaded-CSNPs compared to non-loaded CSNPs exhibited a broad high intensity peak at 2θ = 19-25° implying the entrapment of LGEO within CSNPs. Thermogravimetric analysis (TGA) showed that encapsulated EO was decomposed at a temperature of 252 °C compared to a degradation temperature of 126 °C for pure LGEO, indicating a two-fold enhancement in thermal stability of encapsulated CSNPs. Differential scanning calorimetry also proved the physical entrapment of EO into polymeric matrix of chitosan. In-vitro release study showed a time- and pH-dependent release of EO into release media demonstrating a three-stage release behavior with a rapid initial release of EO, followed by a steady state migration of EO from its surrounding envelope at the later stages. Antimicrobial assay showed strong antimicrobial properties of free form of LGEO against the bacteria (both gram positive and gram negative) and fungi species tested. Moreover, loaded-CSNPs exhibited stronger antibacterial and anti-fungal activities than non-loaded CSNPs.

Sugar beet pectin extracted by ultrasound or conventional heating: a comparison.

The yield and quality of sugar beet pulp pectin obtained by ultrasound-assisted extraction (UAE) were compared to those obtained by conventional heating. Extraction temperature (70-90) °C, extraction time (2-4) h and pH (1-1.5) were considered as the variables for the conventional extraction while ultrasound frequency (20-60) kHz, time (10-30) min and amplitude (60-100%) were considered as the variables for UAE. The optimal conditions for maximum yield of pectin for conventionally and ultrasonically extracted pectin were determined by the central composite design and the Box Behnken design, respectively. The optimum conditions of conventional extraction were the temperature of 90 °C, time of 4 h and pH of 1. The optimum conditions of UAE were ultrasound frequency of 20 kHz, time of 10 min, and ultrasound amplitude of 96%. Extraction using the optimized conditions of conventional heating and UAE achieved the best yield of 20.75% and 20.85%, respectively. The degree of methyl esterification, ferulic acid content and molecular weight of UAE pectin were higher than conventionally extracted pectin but the content of galacturonic acid in UAE pectin was lower than that of conventionally extracted pectin. The infrared spectra of both pectins revealed the occurrence of polysaccharide component. The pectin achieved by UAE had higher lightness value than conventionally extracted pectin, confirming its application in different products partially in bright food products. The UAE pectin possessed higher viscosity than conventionally extracted pectin. The addition of UAE pectin increased all of the DSC gelatinization parameters. Overall, UAE could be a promising scalable and economical approach to obtain pectin with unique characteristics.

Chitosan Nanoparticles as a Promising Nanomaterial for Encapsulation of Pomegranate (Punica granatum L.) Peel Extract as a Natural Source of Antioxidants.

The encapsulation of pomegranate peel extract (PPE) in chitosan nanoparticles (CSNPs) is an advantageous strategy to protect sensitive constituents of the extract. This study was aimed to develop PPE-loaded CSNPs and characterize their physical, structural morphology, antioxidant and antimicrobial properties. Spherical NPs were successfully synthesized with a mean diameter of 174-898 nm, a zeta potential (ZP) of +3-+36 mV, an encapsulation efficiency (EE) of 26-70%, and a loading capacity (LC) of 14-21% depending on their loaded extract concentrations. Based on these results, CSNPs with chitosan:PPE ratio of 1:0.50 (w/w) exhibited good physical stability (ZP = 27 mV), the highest loading (LC = 20%) and desirable encapsulation efficiency (EE = 51%), and thus, selected as optimally loaded NPs. The FTIR analysis of PPE-CSNPs demonstrated no spectral changes indicating no possible chemical interaction between the PPE and CSNPs, which confirms that the PPE was physically entrapped within NPs. Moreover, FTIR spectra of pure PPE showed specific absorption bands (at 3293-3450 cm-1) attributed to the incidence of phenolic compounds, such as tannic acid, ellagic acid and gallic acid. Total phenolic content (TPC) and antioxidant analysis of selected CSNPs revealed that the encapsulated NPs had significantly lower TPC and antioxidant activity than those of pure PPE, indicating that CSNPs successfully preserved PPE from rapid release during the measurements. Antibacterial tests indicated that pure PPE and PPE-loaded CSNPs effectively retarded the growth of Gram-positive S. aureus with a minimum inhibitory concentration (MIC) of 0.27 and 1.1 mg/mL, respectively. Whereas Gram-negative E. coli, due to its protective cell membrane, was not retarded by pure PPE and PPE-CSNPs at the MIC values tested in this study. Gas chromatography-mass spectroscopy analysis confirmed the incidence of various phytochemicals, including phenolic compounds, fatty acids, and furfurals, with possible antioxidant or antimicrobial properties. Overall, CSNPs can be regarded as suitable nanomaterials for the protection and controlled delivery of natural antioxidants/antimicrobials, such as PPE in food packaging applications.